Scientists whose Antarctic expedition became trapped in sea ice finally returned to dry land yesterday, apologising for the disruption and facing questions over who will pay for the international rescue mission. The scientists were among the 52 passengers plucked by helicopter from their stranded Russian ship, the Akademik Shokalskiy, on January 2 after Chinese and Australian icebreakers failed to cut through the ice to rescue them. A helicopter from the Chinese ship, Xue Long, transferred them to the Aurora Australis, which docked in Hobart. The rescue, estimated to have cost up to A$2.4 million (HK$16.3 million), prompted harsh criticism from some quarters because it diverted resources from other scientific programmes in Antarctica's summer. Expedition leader Chris Turney said the attempted rescue had been a great example of the international co-operation possible in the remote and inhospitable Antarctic. "We are terribly sorry for any impact that might have had on fellow colleagues, whose work has been delayed from the operation, but any experienced Antarctic scientist knows that's an inherent risk," he said. The Shokalskiy became stuck near Commonwealth Bay, about 100 nautical miles east of the French base Dumont d'Urville, on December 24 and endured a fierce blizzard soon afterwards.